Intermittent claudication in peripheral arterial disease
Intermittent claudication is cramping or aching leg muscle pain that comes on with walking and is relieved by rest, because narrowed arteries cannot supply enough blood during exercise.
Remember
Intermittent claudication is leg muscle pain brought on by exercise and relieved by rest, because atherosclerotic narrowing limits the blood flow to working muscles. Pain that continues at rest points to a more advanced stage.
Intermittent claudication is pain, cramp or aching in the leg muscles that comes on with walking and is relieved by rest. The pain is intermittent because it comes and goes with activity. It is usually felt in the calves.
The usual cause is atherosclerosis, in which a build-up of fatty plaque in the artery wall narrows the arteries. In the leg, this narrowing of the arteries is peripheral arterial disease.
While you rest, narrowed arteries can still deliver enough blood to the leg. Walking makes the muscles need far more oxygen, but a narrowed artery cannot increase the flow to match. The muscle becomes ischaemic (short of blood and oxygen) and aches. When you stop, demand falls, supply catches up and the pain settles. This is why the ischaemia is described as reversible.
The pain returns after about the same distance each time, so the claudication distance is a useful measure of severity. The pain usually settles within about 10 minutes of rest.
Claudication develops gradually with exercise and does not appear suddenly at rest. If the disease progresses, pain can begin at rest, which signals critical limb ischaemia, a more advanced stage.
Key facts
- Symptom
- Aching or cramping in the leg muscles, usually felt in the calves, that appears on exertion and goes away with rest.
- Cause
- Atherosclerosis narrows the leg arteries, so during exercise blood flow may not rise enough to meet the oxygen demand of the working muscle.
- Mechanism
- Walking raises the oxygen demand, the muscle becomes ischaemic and hurts, and resting lowers the demand so that the pain settles.
- Pattern
- The pain returns after about the same walking distance each time and usually settles within about 10 minutes of rest.
- Nature
- It comes from chronic narrowing of the arteries, and it develops gradually rather than suddenly.
- Escalation
- Pain at rest suggests critical limb ischaemia, whereas sudden severe pain with a pale, pulseless limb suggests acute arterial occlusion.
Exam traps
- Critical limb ischaemia is a more advanced stage of the arterial disease that causes claudication, so it brings pain that continues at rest, not pain that settles within minutes of stopping.
- A deep vein thrombosis (a clot in a deep leg vein) typically brings throbbing pain and swelling in one leg. Claudication pain, by contrast, returns after about the same walking distance each time and usually settles within about 10 minutes of rest.
- Incompetent venous valves let blood flow backwards in the leg veins, giving aching and swelling that tend to be worse after long periods of standing and better when the leg is raised. That is not the pattern of claudication, where the pain comes on after about the same walking distance each time.
Read the full notes
Tested in 6 SimpleMed+ questions
Practice it in Cardiovascular System, with the answer and a full explanation after every question.
Practice these questions